Abstract

Antimicrobial resistance is raging, but large size of India limits comprehensive exploration. This demands a sample like sewage, which could represent a large population and is often reported to harbor resistant microbes. Here, we did pan-India sewage sampling and studied the antibiotic resistance pattern in the microbial community. We used culture-based antibiotic susceptibility assays and estimated the level of antibiotics present at each site. We found high antibiotic resistance across all cities of India with more diversity of resistance profiles in bigger cities as compared to smaller ones. Bacillus and Pseudomonas were the most common, predominant resistant genera across Indian cities and many sites harbored multi-drug resistant phenotypes. Antibiotic concentrations were below recommended limits at all sites and thus high resistance is not likely caused solely due to antibiotics. Sewage proved to be a good representative for rapidly studying antibiotic resistance in a big country and for similar epidemiological strides.